Field of the Invention
The present invention relates generally to light-emitting diode (“LED”) area lamps using a plurality of LEDs operating at relatively high wattages in commercial applications including warehouse, high bay and parking lot applications and more particularly, to housings incorporating features for cooling such lamps.
Background of the Invention
Solid state lamps or lights utilizing arrays of LEDs are now gaining favor for use in a variety of applications including general indoor and outdoor area lighting of commercial warehouse, high bay and parking lot facilities, among a growing list of commercial and residential applications. Lighting systems utilizing LED arrays offer a longer lasting, more efficient alternative to conventional area lights such as incandescent, fluorescent and halogen lights.
LED based lights have certain drawbacks, however. In particular, the high level of luminescence required in an area lamp cannot be achieved by the use of a single LED. In order to achieve luminescence comparable to prior art incandescent, fluorescent and halogen lamps, numerous LEDs are required. Therefore, LEDs have been fabricated in arrays or modules where each module may comprise dozens of individual LEDs. Multiple modules are then packaged within a single lamp housing.
LED lamps comprising multiple modules composed of a plurality of LEDs tend to generate a substantial amount of heat. LEDs are well-known to be sensitive to heat. Excessive heat typically causes the structures forming an LED module to fail or to deteriorate and therefore negatively affect the brightness and service life of the LEDs. LEDs are prone to heat related failures because the circuit boards to which they are mounted are generally poor conductors of heat. LED lamps used in area lighting applications frequently operate within the range of 100 to 300 watts. Operation at such wattage levels is sufficient to degrade the individual LEDs which make up the modules contained in the lamp unless adequate cooling is provided.
The art of LED lamp design is relatively new. While a number of LED lamps featuring a variety of cooling mechanisms have previously been developed, at the present time, no particular design has proven to be superior to other types and the industry has yet to settle on a standardized design. Thus, there remains room for improvement in the art.
Increasing the ability of an LED lamp to dissipate heat allows for the use of higher operational wattages and/or more arrays of LEDs per lamp housing, and thus brighter LED lamps. Accordingly, there is a need in the art for LED lamp housings which include a cooling system to dissipate the heat generated by LEDs operating at high wattages.